Closest approach is on December 19, 2007. Opposition is on
Christmas Eve.

Don't believe the hoax!

There is a message floating around the internet about
an amazingly close Mars opposition where "Mars will be as big as the moon!"
That message is a hoax, and it's full of misinformation. It describes
an opposition that happened in 2003. It's over.
For more information on the hoax, see
my article on
the evolution of the hoax, or the
Snopes.com page.

This year's opposition will not be as close as the
2003 opposition. But here's the good news:
For nothern hemisphere observers, Mars will soar about high in the sky
as it gets -- 80°!

That makes a huge difference in the steadiness of the atmosphere.
Even though the disk of Mars will be quite small, only 15.9"
(vs. 25" in 2003 and 20.2" in 2005),
the steadier seeing may allow use of high magnification, and you
may be amazed how much you can see on this small planet.
It will reach magnitude -1.6 at its brightest.

This opposition is somewhat unusual in that we'll be seeing Mars
nearly equator-on. So we should be able to see both hemispheres
fairly equally, and may even be able to see both polar caps at
once. Mars will hit its equinox (autumnal for the southern
hemisphere, vernal for the northern) on December 9, so the north
polar cap will be very prominent while the southern cap will be
quite small. Throughout December we should be able to see the
hazy "north polar hood" gradually break up to expose the brighter
polar cap beneath.

If you have questions on observing Mars, or answers which you
think belong in a FAQ, please mail.

Mars Observing FAQ

Q. What's an opposition, and why do I care?
A. Opposition is when an outer planet is opposite the sun as seen from earth;
i.e., when it is closest to us. A planet appears bigger at opposition,
and details are easier to see than at other times. In the case of Mars,
the difference in size and visible detail is dramatic.

Note that the month or so after the opposition is also a good time
to observe; although the planet will be starting to recede, it will
be rising earlier in the evening than at opposition,
which makes it easier for most people to observe it when it's high
in the sky.

Q. What sort of equipment do I need to look at Mars?
A. Just about any telescope will do. I've seen some detail on Mars,
during the 1997 opposition, with my 4.25" f/4
reflector, though that's certainly not an ideal planetary telescope.
A good 6" f/8 reflector or 4" refractor should show
a lot of Mars detail if the air is steady and if the telescope is in
good collimation. I've also gotten excellent views of Mars through
big dobsonian reflectors: although a clock drive is convenient
for high magnification observations, don't let that stop you if
you happen to have a dob. In 2003 I've done most of my
observing so far with my homebuilt 8" dobsonian.

Binoculars won't show
you any more than you see with the naked eye: just a bright red point.

Steady air and magnification are more important than telescope
aperture, ultimately;
you'll have the best luck when Mars is high in the sky, and it may
help to find a location at high elevation or at least one where
you're not looking over houses, cars or asphalt.

Q. Do I need filters to observe Mars?
A. No, but they can sometimes help in bringing out detail.
They're especially helpful if you have an inexpensive refractor
which has some chromatic aberration (meaning that it shows some
colored fringes around bright objects): filters can dramatically
cut down the color fringing.
See specifics on the
ALPO page.

Q. What can I see with a small telescope?
A. Hellas (a bright impact basin), some dark features like Syrtis Major,
Mare Erythraeum, Mare Acidalium, and Niliacus Lacus,
more subtle dark features like Margaritifer Sinus, Sinus Sabaeus,
Lacus Solis (the "Eye of Mars"), and the polar caps.

With filters, you can sometimes see clouds and hazes of
various types. With exceptional seeing, there are many other light
and dark features which become visible, and you can look for details
on the edges of the features, and for clouds over the Tharsis volcanos.
You may even see parts of Valles Marineris, near Lacus Solis.

Sorry, you won't see canals -- there aren't any. But there's plenty
of other stuff to look at!

Q: Why can't I see anything at all?
A: Mars is small. Really small. The details are smaller still. You
really have to practice and have patience. The details will come,
but don't expect them to be easy.
Try for the polar cap first: that's usually the easiest to see.
Then try to see some dark markings on the planet.
The more you observe
the planet, the more you'll learn how to see the detail on it.

Q. How can I train my observing skills?
A. Observe a lot -- start well before the opposition if you can,
even if Mars is small or low in the sky. That way, by opposition
you'll be ready to see all the detail which is there.

Also, try sketching the detail that you see -- even if you don't
consider yourself an artist (I'm certainly not),
sketching planetary detail really helps
you think about what you're seeing, as well as being fun in its
own right.

Q. How do I figure out what part of the planet I'm looking at
and how it's oriented at the time when I'm looking?
A. That's one of the tricky parts of observing Mars, especially during this
opposition when the polar cap is expected to be inconspicuous.

One way is to use a Mars globe, if you can find one (see the Links
section for some suggestions).

The other, and easier, method of orientation is to use a computer
program. See the software links below for programs which show Mars
rotated correctly for a particular time and date.

Q. Can I see Mars' moons?
A. The moons should, in theory, be visible in large amateur telescopes (say,
a 10" or so), but they're quite difficult due to their closeness to the
high surface brightness image of Mars.
Phobos is brighter, but Deimos is farther from Mars.
It helps to move Mars just out of the field, or to use an "occulting
bar" in the eyepiece to block out the brightness of Mars.
It's a challenge, but it's definitely possible!

USGS
Mars Maps & Globes
This site has kits to download and build an excellent Mars globe from
a PDF made from Mars Viking and Global Surveyor mosaics. Excellent!
The Mars Viking Image Mosaic Globe (flower petal image, 3.3Mb PDF) is
the best for observers.

Making
globes of the planets, a complete set of planet globes images,
complete with two perl options for making your own (one is a GIMP
plug-in, the other is a standalone script).

JPL's space simulator
Views of any solar system object as it looks at a specified time.
Unfortunately, it doesn't show much detail on Mars so I haven't
found it very helpful for figuring out which features are pointed
toward us at a given time. No feature labels.

Places to buy Mars Maps and Globes

Here's everything I can find on sources for Mars maps and globes --
not much, so please let me know if you have something to add!
(Thanks to Mike Koop for a lot of the research already here.)

Replogle makes my favorite Mars globe; it's 4", shows albedo features
and used to be sold in toy stores in an inexpensive set with a
(marginally useful) moon and (fairly poor) earth globe.
Unfortunately it has become very difficult to find; I've heard that
it's possible to buy these from Replogle in quantity and someone may
be reselling them on ebay, so try searching ebay for "mars globe".

Inflatable Mars globes: I got one of these at RTMC.
It doesn't have many features
labelled, but you can correct that with a magic marker.
Hint: stick a red flashlight up against one side of it and the whole
balloon turns an eerie red-orange -- great for public events.
I bought mine from the Astronomy
To Go booth at RTMC; they don't have an online store but
apparently you can mail order via phone or email.

Software packages which shows Mars' rotation and surface features

Any decent planetarium program will show Mars' location in the sky,
but not many show its surface features and correctly calculate
which features are visible at a particular time.
Here are some which do:

Starry Night
Mac and Windows Planetarium program (not free) known for its pretty images,
and the newer versions offer excellent Mars support (you may have
to turn on the "Planetary Atmospheres" feature).